Diesel additive can be toxic to liver

Emma Woollacott, 18th November 2011

A common additive in diesel fuel can cause liver damage, say researchers at Marshall University.

They've shown that nanoparticles of cerium oxide — a common diesel additive used to increase engine fuel efficiency — can travel from the lungs to the liver and cause toxic effects.

The team found a dose-dependent increase in the concentration of cerium in the liver of animals that had been exposed to the nanoparticles. And these increases in cerium were associated with increased amounts of liver enzymes in the blood, along with histological evidence consistent with liver damage.

As well as its use as a fuel additive, cerium oxide's also widely used as a polishing agent for glass mirrors, television tubes and ophthalmic lenses.

Some studies have found that cerium oxide nanoparticles may also be capable of acting as antioxidants, leading researchers to suggest they might potentially be used in the treatment of cardiovascular disease, neurodegenerative disease and radiation-induced tissue damage.

"Given the ever-increasing use of nanomaterials in industry and in the products we buy, it is becoming increasingly important to understand if these substances may be harmful," says Dr Eric Blough, director of Marshall’s Center for Diagnostic Nanosystems.

"To our knowledge, this is the first report to evaluate if inhaled cerium oxide nanoparticles exhibit toxic effects in the liver."

The team says that the potential effects of nanomaterials on the environment and cellular function are not yet well understood.

"Our next step is to determine the mechanism of the toxicity," says PhD student Dr Siva Nalabotu.